Multicolor job or proof press



Dec. 22,1953

Filed Feb. 17, 1951 J R. PARRISH MULTICOLOR JOB OR PROOF PRESS 3 Sheets-Sheet l Dec. 22, 1953 J R. PARRIsH 2,563,254

MULTIOOLOR JOB OR PROOF PRESS Filed Feb. 17, 1951 5 Sheets-Sheet 2 Dec. 22, 1953 J R. PARRISH 2,663,254

MULTICOLOR JOB OR PROOF PRESS Filed Feb. 17. 1951 5 Sheets--Shee'I 3 Patented Dec. 22, 1953 MULTICOLOR JOB OR PROOF` PRESS .l Russell Parrish, Des Moines, Iowa, assignor to Meredith Publishing Company, Des Moines, Iowa, a corporation of Iowa Application February 17, 1951, Serial No. 211,472

6 Claims.

This invention relates to a multi-color printing press for use either in the proofing of curved rotary press plates or for job printing, although the invention is not necessarily limited to those uses. This particular application is a continuation-inpart of application `Serial No. 51,400, iiled September 27, 1948, now abandoned.

Large rotary presses for printing magazine color sheets may, for example, print hundreds of thousands of the same color sheets on one run. These large presses take considerable time to set up for printing, and this so-called make-ready time may take one hundred or more man-hours before the press can be started. This is expensive not only because of the time in labor, but also because the press is not producing during the make-ready time. Furthermore, if there is anything wrong with one or more of the printing plates, it does not show up until a run is started, and thereafter1 if even a single plate must be removed for correetion, the press must be shut down all during the time the correction is made. For the above reasons, proof presses have been devised to test the plates prior to their being disposed on the main press.

The available proof presses also have certain disadvantages. Under present methods of curved plate proong, a single color proof is pulled by hand ofi' each plate. Usually these are in black ink, so that neither the color may be proofed, nor may the iinal result in two, three or four colors be seen until the main press is run.

is therefore, an object of the invention to provide an improved multi-color press which may be used as a proof press.

It is also an object of the invention to prou vide a multi-color proof press in which plate register may be determined prior to sending the plates to the pressi-oom and prior to attaching them t0 the main press. Therefore, if certain plates must'ee cut and leveled, this may be done in advance, thus reducing the make-ready time on the main presses. If necessary to make new plates, they may be ordered when proofed instead of waiting until the run is started.

it is further an object of the invention to provide a multi-color proof press on which the interchangeability of spare plates with regular sets may be checked in advance of press runs, thus saving press time during a run.

l't is an additional object of the invention to provide a multi-color proof press in which the results to be obtained from the use of certain inks, the comparative tone intensities for eachj color and thev selection of the proper underlay (Cl. lOl-174) may all be checked in advance of placing theY plates on the main press.

It is a further object of the invention to pro- Y quence and where the proof is printed as thek iinished product will be, and not reversed.

With respect to job presses under present methods, small runs of multi-color work are very expensive and time consuming. On present job presses, each color is placed on a sheet separately and allowed to dry before the next color is put in. Two-color presses are quite common but require two runs for four-color work, with a wasted time interval between colors. Drying usually takes from one to two days. Furthermore, paper shrinks and expands due to varying temperature and humidity conditions, so thatperfect register is very seldom obtained. In addition, it is impossible to see the iinal result until the last color is placed on the sheet. Large high speed multi-color presses are too expensive for the average job printer.

It is an object of the invention, therefore, to provide a multi-color press which is adapted to job printing and which is relatively inexpensive.

It is another object of the invention to provide a job printing multi-color press on which the iinished result may be seen at the beginning of the job, on which make-ready work may be done at one time and on which better quality of multi-color printing from a register standpoint is obtained.

It is also an object of the invention to pro- Vide a multi-color job press on which the waits ing time for drying between colors is eliminated and the total running time is decreased.

It is a further object of this invention to provide a multi-color job press having aplurality of printing plates, each of 4a diierent color, upon one cr more plate cylinders, which 4job press prints the colors in the same specified sequence and upon the saine specified portions of all the sheets being printed.

lt is a very important object of the invention to provide a multi-color press in which the correlation between the diameters of the one or more plate carrying cylinders with the diameter ofthe impression cylinder is such that the ratio between the impression cylinder diameter and the diameter ci the plate cylinder or cylinders is an aliquant number. Tin other words, the ratio must be such that when the smaller number is divided into the larger number, a iractionAis always left over. When such ratio obtains, the successive various color plates on the plate cylinder or cylinders successively contact one and the same area on the impression cylinder, whereby a sheet oi paper placed on the particular area will receive successive imprints of diiierent colors always in the same predetermined sequence; Y

it will be recognized that the ratio between the circumference ci the impression' cylinderY and the circumference ci the plate cylinder is the same aliquant number as the ratio of the diameter oi" the impression cylinder and the diameter oi the plate cylinder, since the circumference of av cylinder is merely e times the diameter. Since segments ci the impression cylinder and plate cylinder must repeatedly coincide in predetermined sequence during a printing run, the circumference may be defined in terms oi these segments and a unit o circumferential length will be denned in terms or" an impression suriace on which the sheet to be printed. is mounted, or in terms of a plate su 1iace which carries the inl. This unit oi circumferential length is an aliquot part of both the circumference oi the impression cylinder and the circumference oi the plate cylinder. in this specincation, the relationship oi impression suriaces to plate surfaces will be ta zen up and described, as such relationship is simpler than a discussion or" the relationship of the diameters of the impression and plate cylinders.

W ith these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my device whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawings wherein:

Figure l is a perspective view of a multi-color press illustrating one embodiment of the invention;

Figure 2 is a diagrammatic view of the press shown in Figure l, also showing the relative position of the press to the blank stock supply and to the printed stock;

Figure 3 is a diagrammatic view oi a press constructed in accordance with a second embodiment of the invention;

Figure Il is a schematic view of the grippers and the actuating mechanism therefor, and is taken looking upward irom beneath the impression cylinder il as shown in Figure 3;

Figure 5 is a diagrammatic view of a gripper in closed position;

Figure 6 is a diagrammatic View of a gripper in an open position;

Figure "l is a diagrammatic view of the tumbler used to open and close the grippers showing the position of the tumbler just before it closes the grippers;

Figure 8 shows the tumbler just after the grippers are closed;

Figure 9 shows the tumbler just before the grippers are opened;

Figure 10 shows the tumbler just after the grippers are opened;

Figure l1 is a side elevation of the multi-color job and prooi press shown in Figure 3, illustrating an operating mechanism and typical cam arrangement ior reciprocating the tumbler actuating pins;

Figure 12 is a view of a portion ci the operating mechanism for the tumbler actuating pins and is taken on line i2-l2 of Figure 11;

Figure 1S is a detailed drawing of a cam shown inFigure 1 1;

Figure le is a side elevation of the multi-color job and proof press shown in Figure 2, illustrating an operating mechanism and typical cam arrangement for reciprocating the tumbler actuating pins;

Figure 13 is another View oi the operating mechanism and gear-arrangement ior the tumbler actuating pins, and is taken on line lt--l of Figure v1:4.Y

Referring to the drawings, the following general observations are true with respect to the embodiments of the invention shown. As is true with any other job or proof press utilizing rotary plate cylinders, the diameter of the plate cylinder is determined by the dimensions of the press over which the plates are made to nt. Therefore, in speaking of ratios between the impression cylinder diameter and the plate cylinder diameter, the plate cylinder diameter will always be the determining factor. ln some designs, the plate cylinder may be larger than the impression cylinder, and in others the impression cylinder may 'ce larger than the plate cylinder.

Although exact position ci the plate cylinders around the impression cylinder is uni portant from the standpoint of many oi the iinciples involved herein, the plate cylinders must preferably be positioned within a limited region so as to provide for opening of the grippers to discharge the printed sheet and later closing oi the grippers for icliing up a fresh sheet within a-limited range of rotation of the impression cylinder. 1t is. also important that the sheet being discharged from the impression cylinder be clear of the printing plates to the greatest extent posible, so that there is little chance ci relative motion between the sheet and the last printing plate. The positioning of the plate cylinders with respect to the points where the sheets are picked up and discharged from the impression cylinder is shown in Figures 2 and 3. Since more than one color of inl: is to be applied to each plate cylinder, the inlrng or form rollers may be engaged and disengaged by means or a cam (not shown) on the plate cylinder in a manner well known in the art.

As stated above, the designs shown herein diifer from other printing presses -iy utilizing various fractional gearing ratios or diameter ratios, which ratios must be oi some other value than 1:1. When the impression cylinder is run with the plate cylinder at any ratio other than ill, the smaller cylinder will contact diiierent portions of the larger cylinder at each successive complete turn of the smaller one. 1t is also to be noted that in each design the paper sheet to be printed is carried by the surface oi the impression cylinder. Therefore, for example, if the ratio is 3:2, a certain portion ci the smaller cylinder will contact a diierent portion oi the larger cylinder during each three revolutions of the smaller one. During the following three revolutions, this same cycle will be repeated in the same order. In such a case, by dividing the circumference of the smaller cylinder into two equal portions, and of the larger cylinder into three equal portions, the arc of each segment of both cynnders wm be tne'sameulngth n w'il'liaiso and will be even when the number Vof colors isA odd. Y

There is a critical relationship among the following quantities: The number of printing plates (or colors to be printed), the number of plate cylinders, the number of sheets taken onto (or discharged from) the impression cylinder during a full cycle, theinumber of impression surfaces on the impression cylinder, and the number of revolutions of the impression cylinder necessary to have each printing plate register once with each impression surface (the number of revolutions of the impression cylinder per cycle). This relationship may be expressed in the form of an equation or formula which is generic to all the embodiments of the invention described herein or constructed in accordance with the principles herein set forth. That equation or formula is:

Number of sheets taken onto the impression cylinder during a cyc1e Number of colors Number of plate cylinders Number of revolutions of the impression cylinder per cycle Since each impression surface takes on one sheet during each cycle, it will be seen that:

The number of sheets taken onto the impression cylin= der during a cycle Thus, the generic equation can be more simply Number of impression X surfaces Number of impression surfaces written as:

Number f C00IS Nurnber of revolutions of Number 0f plat@ the impression Cylinder cylinders It should be pointed out that if more than one plate cylinder is used, the colors must be equally divided among the plate cylinders for the equation to obtain.

Referring specically to Figures l. and 2 for a description of the iirst embodiment of the invention, numeral I l designates vertical frame members for a rotary press, and numeral l designates a combination bed plate and shelf upon which sheets are delivered to the impression cylinder. A shelf I3 is provided for receiving the printed sheets from the impression cylinder, which sheets have been given the numeral The impression cylinder is shown generally at ld and the plate cylinders are shown at l5 and l. The impression cylinder is rotated through a shaft il secured thereto and provided with suitable bearings in the frame members l l. The shaft I'I may be rotated by hand or `by any suitable source of power.

A gear I8 is secured to one end of the impression cylinder` Iii and isrotated by the shaft il. The plate cylinder i5 is provided with a gear i9 and the plate cylinder Ie is provided with a gear 2|, the gears lil and 2i each being of the same size and both being'smaller thanthe gear i8. The ratio of the pitch circle oi gear it to the pitch circle of gears i9 and 2l is'3:2. The gears l5 and 2| are rotated by gear I 8. The plate cylinders I5 and IS are provided with shafts B and 23, respectively, which are supported in suitablcbearings in the frame members I I.

Movable sheetV grippers Z are provided in Va recess 25 in the impression cylinder it. In thisembodiment, three sets oi grippers lill are provided, and these grippers piola up individual sheets 3B from the shelf I2 `and release the printed sheets S'Ilaat the propertime onto the shelf I3,

that is, when the printing cycle is completed. The pickup and release of the sheets is effected by cam means which will .be described hereinafter. y

The impression cylinder Ill is divided into three segments 25, 2l and 28, upon which the paper sheets are retained during the color printing op,n eration. The plate cylinder l5 is provided with two printing plates 3| and 32 with undercut por-,

tions 38 therebetween. The plate cylinder it is likewise provided with two plates and Sil, leav' ing undercut portions 3e therebetween. AThe plate cylinder I5 is ,provided with two sets of inking rollers sii and the plate cylinder' I 6 is provided with two sets of inlring rollers AEl. Each of the inking rollers places a diierent colorV on the plates at the proper time, in a manner well understood in the art. The spaces between the plates provide space to lower the inking rollers to inking position without inking the wrong plate and still fully ink the succeeding plate. The spaces 38 also provide for lifting of the inking rollers after the inked plate has passed without inking part of the next plate.

Assuming that the four colors to be used are yellow, red, blue and black and are printed in that order upon each sheet, plate 33 is the plate for printing the yellow color; plate 32, red; plate 34, blue; and plate 3l, black. lt will be obvious that as the impression cylinder lll is rotated, four colors may be proofed in one operation which comprises two revolutions of the impression cylinder. One of the sets of inking rollers 3S is adapted to supply red ink. to plate 32 and another set of inking rollers 35 is adapte-d to supply black ink to plate 3|, in a manner well known in the art. Similarly, one of the sets of inking rollers 37 is adapted to supply yellow ink to plate 33 and the other set of inking rollers 37 is adapted to supply blue ink to the plate 3s.

The ratio of the circumference of the impres sion cylinder to the circumference of the plate cylinders is 3:2. One-third of the circumference of the impression cylinder includes `one of the impression surfaces plus a recess 25 within which grippers 2li are mounted. The arcuate length of surfaces SI, 32, 33 and Btl on plate cylinders I5 and IS is substantially the same as the length of the impression surfaces 25, 2l and 2t on pression cylinder It. The arcuate length of recessed portions 38 and 3S on plate l5 and It is substantially the saine as the arcuate length of the recesses 25 in impression cylinder I4. Two recessed portions .is and are provided in each plate cylinder, one of said recessed portions 38 and 35 being associated with each plate portion 3I, 32, 33 and Ell. rihe Varcuate length of the printing plates is substantially that of the arcuate length of the impression suraces, and the arcuate length of recesses 33 and et is the same as the arcuate length of the recesses 25 in the impression cylinder, so that upon rotation of the cylinders the impression surfaces and the printing plates will always register with each other.

Figure 3 shows an embodiment which is particularly adaptable for a job press to provide four-color printing on a press having one plate cylinderl and one impression cylinder. In this case the impression. cylinder shown at 4l is smaller; than the plate cylinder shown at 52,. The ratio of the circumference of the plate cylinder to thecircumference of the impression cylinder in this case is 4:3. This design for four-.color printing is limited to printing by plates having a cur-ved length not exceeding one-quarter the circumference of the plate cylinder 52. Only one.- third of the impression cylinder surface is used for each impression, and four revolutions of the impression cylinder will effect the transfer of all four'- colors.

As shown inv Figure 3, the impression cylinder 4l provided with three sets of grippers i2 disposed in recess i3 for picking up and releasing sheets of paper 30, in the same manner as described with respect to Figures 1 and 2. Three impression receiving surfaces et, l5 and le are provided.

A stack of blank sheets t is shown at al, which sheets are individually fed, in a manner well known in the art, over a surface iii to a position Where they will be picked up at the proper time by the grippers 42. The completed or printed sheets are also fed, in a manner well known in the art, over a surface l to a printed stack shown at 49. Sheet t@ is only released after four revolutions of the impression cylinder, so that all four of the plates shown at 53, 54%, 55 and 55 on the plate cylinder will .have contacted each sheet on the impression cylinder. The plates on the plate cylinder 52 are slightly spaced from each other to provide an undercut portion 5l therebetween. The undercut portion 5'! is of the same circurnferential length as the recess es in the impression cylinder and is positioned to register with this recessed portion d3 upon revolution of the cylin ders, so that the printing plates will always register with the impression surfaces on the impression cylinder 4l. Sets or inking or forming rollers shown at 58, 59, eil and di, one for each color, are provide-d and are operated in a manner stated hereinbefore, to apply the proper color ink at the proper time to each of the printing plates on plate cylinder 52.

For the purpose of this descriptiom'it will be assumed that the color oi the ink carried by printing plate 53 is red; plate tid, yellow; plate 55, black; and plate 5S, blue. It will also be assumed that the printing cylinder 52 rotates ina clockwise direction and the impression cylinder t! rotates in a counterclockwise direction.

Referring nowv more particularly to the grippers which are associated with the impression cylinders to retain the sheets to be printed upon the impression surfaces of the impression cylin der, a plurality of the grippers [l2 are mounted on a shaft 62, which shaft is journalled at points 63 and 6d, illustrated in Figure 4. One end of the shaft B2 extends beyond the point where it is `icurnalled, as at 55. This extended end 65 of. shaft 62 has a tumbler lit xedly mounted thereon. The opening and closing of the grip?v pers 4Z is accomplished by arcuately moving the tumbler 66 about the axis o1 shaft 6.2, resulting in the arcuate movement of shaft t2 which is.

xedly secured to the tumbler Sie. Figures 5 and G respectively, show the closed and openedposis tions and indicate the range of arcuate move-Y ment of grippers drencompassed in the gripping and releasing of the sheet to be printed.

The tumbler as illustrated in Figures '7, 8, 9 and includes a central body portion from which extends a pair of spaced iingers 5l' which form a pocket 5B therebetween, which pocket et is located to one side of the point of securement of tumbler 63 to shaft 62. A second pair of fingers 65 also extends from the central body portion and bounds a pocket 1E! located diametrically opposite the pocket 63.

lit to operate the grippers 3g to opened or closed position.

i portion of the frame of the proof press is designated at 'i3 and upon this frame the tumbler actuating pins and actuating mechanism therefor are mounted. Figures 11 and 12 illustrate an operating mechanism for the tumbler pins that may be used with the form of job and proof press shown in Figure 3. The grippers on proof presses usually are operated manually without the use of tumblers. Figures 1li and 15 show the type of mechanism that is used to actuate the tumbler pins for the form of job and proof press shown in Figures 1 and 2. For illustrating purposes, the actuating mechanism for the tumbler pins as shown in Figures 14 and 15 will be described.

Referring more specifically to Figures 14 and 15, the pins 'El and 'i2 are mounted in the frame structure "i3 and are normally biased to a withdrawn position as is pin il, which in Figure 15 is shown in full lines. rilhe position when extended is shown by dotted lines and indicated by lia. The pins 'il and l?. are biased in the withdrawn position by means of springs lil which are seated in pockets 'i5 in frame lt. A shoulder l on pins il and l2 cooperates with the springs i4 in a well known manner to bring the springs 'lll in operating relation with the associated pin.

The pins 'll and l2 are engaged at their outer ends thereof and are respectively thrust forward by means of bell cranks 'il and 'it which are pivoted respectively at it and Eil upon ears 3l and 82 projected from the frame 13. These bell cranks 'H and lit are respectively actuated through push rods BS and dit which have cam followers 35 and 8d at one end thereof rolling over the surface of earns lil' and 8S. The springs lil serve to maintain the cam followers te and 35 constantly in engagement with the surfaces of the cams 8l and 85. The push rods 5t and are slidingly journalled respectively in blocks 83a and dita. which project from the frame lil.

The cams 8l and dii are mounted upon the same shaft, which shaft rotates at an R, P. M. with respect to the R. l?. M. of the impression cylinder in the ratio of 3:4. in the form of device shown in Figures 11 and 12, the cams il and 38 are mounted on shaft te which is the shaft upon which the plate cylinder 5-2 is mounted. As such, the cams rotate at the same speed as the plate cylinder 52.

1n the form` of the device shown in Figures 14 and 15, the cams tl and @d are mounted on an auxiliary shaft B5 which is suitably journalled in frame 13. The shaft St is driven at a speed onehalf as great as the speed of rotation of the plate cylinders l5 and IB. The operable connection between the plate cylinders and the auxiliary At desired intervals these pins 1|.

9 shaft 90 is shown in Figure 15 as comprising a gear 9| mounted on the shaft 22 of plate cylinder I and a gear 93 mounted on the auxiliary shaft Si). The ratio of the pitch circles of gears 9| and 93 is 1:2 which means that gear 93 will rotate only once for every two rotations of gear 9i.

It will be seen that in the form of the inven-v tion illustrated. in Figures l and l2, the impression cylinder makes four revolutions forV every three revolutions of the plate cylinder. In the form shown in Figures 14 and 15, the ratio of rotation of the impression cylinder to the plate cylinders during a complete cycle is 2:3 but the step-down gear ratio of gears tl and e3 causes auxiliary shaft 9G to be rotated at one-half the speed of shaft 92. This means that the rate of rotation of the impression cylinder to the auX- iliary shaft El is 2:11/2, which when stated in whole numbers is the same as the ratio 4:3. By the simple expedient of varying the speed of rotation of an auxiliary shaft with respect to the speed of rotation of the plate cylinder, the sam-e speed relationship between the impression cylinder and the cam shaft, upon which the cams 3l' and S3 are mounted, is obtained.

The location of the tumbler actuating pins 'H and l2 is of great importance, for they must be positioned slightly before the point Yat which the grippers l2 are closed or opened. 1t can be seen by referring to Figures 7, 8, 9, and l0 that, for example, in the closing of the grippers 42, the tumbler et engages the pin 'il at a point before bottom dead center, where, theoretically, the grippers are to close on the sheet to be printed. Then, as the tumbler te continues to rotate about the center of the impression cylinder, the pin ll being fixed, causes the tumbler 655 to rotate clockwise about the axis of the gripper shaft 52, causing the shaft $2 itseli to be rotated. The grippers 42 mounted on shaft t2 move to the closing position which is shown in Figure 5.

As shown in Figure 8, Ythe tumbler 66 has just moved to the closed position of grippers l2 and the gripper sha-ft t2 is just pastbottom dead center at that point. Similarly, the pin 12 must be positioned so that the grippers i2 are opened when the gripper shaft 62 moves past approximately top dead center. It should, of course, be realized that if gripping or discharging of the sheet to be printed is to take place at other than bottom dead center or top dead center, such may be provided for by the correct position'- ing of the tumbler actuating pins.

Operation of the multi-color :fob orproof press In the operation of the multi-color job or proof press shown in Figures 1 and 2, reference is called to Figures 6 andv 7, wherein the tumbler 56 is positioned so that the grippers 42 are open and the pin 'Il is thrust forward into the path of the tumbler 66 so as to close the grippers 42. The tumbler 65 is so positioned that the fingers 6l pass' over the pin 1| causing the pin 'Il to enter the pocket 6B. The pin 7l engages the fingers 6l and causes the tumbler 66 to rotate clockwise about the axis of gripper shaft 52 as the tumbler 66 moves past the pin 'Il in counterclockwise direction. All the time the tumbler 66 is moving past the pin 1l, pin 1| is moving deeper into the pocket 68. The pin 'Il and the gripper shaft 62 are closest to each other when they are locatedupon a radius through the center of rotation of the impression cylinder 114.

As the tumbler 66 continues its counterclockwise rotation about the axis of the impression l plate 3 i cylinder i4, the pin causes the clockwise rotation of the tumbler 8S and the shaft S2 about the axis of shaft S2, thus closing the grippers d2. The pin 'Il also serves to position the tumbler so that the lingers t9 point in the direction necessary to grasp tumbler actuating pin 'i2 when the sheet which is printed is to be discharged. It will be noted that the attitude or" the tumbler t as it leaves pin 1l, as shown in Figure 8, is the same as the attitude of the tumbler t6 when it is just grasping pin '12, as shown in Figure 9, for the purpose of discharging the printed sheet of paper.

Referring to the particular positions shown in Figure 2, after the grippers 2d associated with impression surface 27 have grasped a sheet to be printed, there will be printed upon it the color which is carried by printing plate 33, and thereafter during the first revolution of the impression cylinder Vthe sheet will also have printed on it the` color carried by printing plate 32. Upon the second rotation of the impression cylinder ifi, the same sheet will first engage the printing plate 3d and then engage the printing After the impression surface upon which the sheet to be printed passes plate 3i, the tumbler te, associated with the grippers 2li holding the sheet that has been printed in all four colors, will be actuated by pin l2 which is thrust forward at the correct moment so that the sheet that is printed will be discharged onto the surface i3.

As shown in Figure 2, the grippers associated with the impression surface 27 have just been opened and the sheet on the impression surface 2l is being discharged. As the impression cylinder continues to rotate, the grippers which are associated with the impression surface 2l will reach the position at bottom dead center shown in Figure 2 as now occupied by the grippers asson elated with the impression surface 28. At this point the grippers will be actuated to closing position and will take on a fresh sheet to be printed.

It will be seen that a complete cycle of the impression cylinder includes two complete revolutions of the impression cylinder. rEhe plate cylinders in the meantime are making three complete revolutions, and because of the diiierence in the number of surfaces between the impression cylinder and the plate cylinders, different colors are successively Vprinted upon the same surface during the two revolutions of the impression cylinder. These colors are printed upon the sheet carried by each impression surface in the same sequence, as follows: yellow, red, blue and black. The reason why continuous` oper ation of Vthe impression and plate cylinders is possible with different colors being printed at all times in the same sequence is due to the aliquant ratio between the diameter of the impression cylinder to the diameter of the plate cylinder.

1 In the form of the job and proof press shown in Figure 3, the impression cylinder makes fourV Pisv shown in Figure' 3, thegrippers associatedwith the impression surface 4t* have just been opened and the sheet carried by the impression surface 4E is being discharged to the shelf 5i. As the impression cylinder continues to rotate, the grippers associated with impression surface 4t are closed at bottom dead center of the impression cylinder and will pick upa fresh sheet to be printed. The next sheet to be discharged is carried on impression surface 44 and is shown being printed blue. Upon the next revolution the'sheet on surface 44 will be printed black and then the sheet will be discharged; Impress-ion surface d will then be ready :for a fresh sheet to be printed.

Both of the forms of the job and proof press shown in Figures 2 and 3 are continuous machines which are continually discharging sheets which have been printed andpicking up fresh sheets to be printed. For a single cycle of operation, in the form shown in Figure 3, the impression cylinder rotates four times, during which period three sheets have been discharged from the cylinder and three sheets have been taken on. The number of revolutions of the plate cylinderv during a complete cycle is three. Thus, only a single cam for each of the pins 'l l` and I2 is necessary to actuate the pinsV H and l2, as for each revolution of the plate cylinder each pin is thrust forward only once and thus coopcrates with one of the tumblers to discharge a Sheet and to pick up a sheet.

in the form of the invention shown in Figure 2, three sheets will be discharged andl picked up during two revolutions of the impression cylinder; For every two revolutions of the impression cylinder, the auxiliary shaft S rotates 11/2v times and, therefore, two dametrically oppositely facing cams ill-81 and iis-Sii to actuate each of the pins ll and l2 are necessary so that eachof the pins il and 'i2 will be actuated three times during a complete cycleA of the auXilia-ryshaft 9% which comprises but 11/2 revolutions. t will beA obvious that the rotation ratios of the impression cylinder andthe cams are such that each of the grippers associated with different impression surfaces aree successively actuated, due to the inequality in angular travel between the impression cylinder and the cams.

With respect tol the specific form of inventionshown in Figures 2, 14, and 15, it willV be observed that auxiliary shaft 2t rotates at one-half the speed of the impression cylinder shafts 22l and 23. Furthermore, auxiliary shaft 90 has two'sets of opposite cams mounted thereon for actuating the pins 'Il or l2. By mountingsingle cams for pinsl 1I and 'i2 on shafts 22 and 23, the same result can be obtained. Thus, a cam arrangement similar to that shown in Figures 11 and 1'2 may be` mounted on either impression cylinder shafts ZZ-and 23.

The cams are so designed that the periodv during which one of the pins 'H or 12 is thrust forward is less than the angulardisplacementv of one set of grippers with respect to the other set of grippers. In this way only one set of'gripp'ers will be actuated at a time, and therebythere will be; no inadvertent actuation. of the successive set of` grippers.

This angular relationship is illustrated on the cam shown in Figure 13` which cam is one of those. used in the form oi the device shown in Figures 3, ll and 12. The actuating pin is fully thrust forwardv for about 30 degrees of angular movement of the impressioncylinder;whichcorv 75 impression and; plateV cylinders each being an CIT responds to- 2'21/2 degrees of angularmovement' of the cam. The operating region through which a tumbler passes, where the tumbler may be actuated by a pin, is inA the neighborhood ot 30 degrees oi angular movement ofthe impression cylinder. Thus, the enlargedportion of the cam which actuates the push rods, bell cranksl and pins, encompasses a maximum range of about 1571/2 degrees, which corresponds to an angularA motionon the impression cylinder of about 2li0 degrees. Sincev the spacing between successive sets of grippers is degrees, there is no possibility oi pin *H or l2, upon being thrust forward to actuate one set of' grippers, inadvertent-,lyongaging the tumbler of the next successive'V set of grippers.

Some changesl may be made in the construe-- tion and arrangement of the parts of my multi-- color pressesv without departing from the realspirit and purpose of my invention, and it is myy intention to coverby my claims any modied forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

I claim as my invention:

1. A multi-color printing press comprising a single impression cylinder and at least one plate cylinder each having'segments of equal peripheral length in the surfacesA thereof adapted to register in tangential relation with each other', theA circumferential length of the surfaces of the impression andy plate cylinders each being an aliquot multiple, greater than unity, of the length of' a segment, the circumferential length of a plate cylinder and the circumferential length of the impression cylinder beingunequalf by one segment length, meansr for rotating said impression and plate cylinders at the same peripheral speed, means including'a plurality of printingplates positioned in saidplateV cylinderA segments for printinga plurality of colors greater than the number of platev cylinders, means forretaining a sheet to be printed on each segment ofthe impression cylinder, a feeding stationpast which each impressionI cylinder segmentA passes as theimpression cylinder: rotates, means for feeding sheets consecutively toy anv arithmetical progres'- sion of said impression cylinder segments pass-- ing said feeding station, the number of consecu tive impression cylinder segments skipped be-4 tween one` segment Whichreceives a fresh sheet andlthe next segment receiving afresh sheet being one less than thevnumber ofplate segmentson a single plate. cylinder,l meansk forA discharg ing a sheet from its impression segment after it has registered' with eachof. the: printing: segments onA the printing' cylinders means, i-.or feeding. a

freshxshcet to beI printed onsaid vacated'V impression: seg-menty before said impression segment registers with any other plate segment, whereby fresh. sheets are fed onto said impression, cylinder; continuouslyateqnal, intervals and. whereby printed sheets are. discharged'. from, said impressionA cylinder continuously at equall intervals, andA whereby each of: the sheets carried. by the irnpression cylinder is caused4 to registerl with each ofthe printing plates inthe same predetermined sequence and, beginning with the, same color.

2. A multi-color printing press comprising av singlev impression cylinder and: at least one plate cylinder each having segments of equalperipheral lengtlr inv the surfaces; therem adapted' to.

register in, tangential. relationv witheach. other, theci-rcumierential; length of thek surfaces of the 13 aliquot multiple, greater than unity, of the length of a segment, the circumferential length of a` plate cylinder and the circumferential length of the impression cylinder being unequal, means for rotating said impression and plate cylinders at the same peripheral speed, the ratio of the total number of Segments in the periphery of the impression cylinder to the total number of segments the periphery of each plate cylinder being a fraction of lowest terms, means including a plurality'of printing plates positioned in said plate cylinder segments for printinfy a plurality of colors greater than the number of plate cylinders, means for retaining a sheet to be printed on each segment of the impression cylinder, a feeding station past which each impression cylinder segment passes as the impression cylinder rotates, means for feeding sheets consecutively to an arithmetical progression of said impression cylinder segments passing said feeding station, the number of consecutive impression cylinder segments skipped between one segment which receives a fresh sheet and .the next segment receiving a fresh sheet being one less than the number of plate segments on a single plate cylinder, means for discharging a sheet from its impression segment after it has registered with each of the printing segments on the printing cylinders, means for feeding a fresh sheet to be printed on said vacated impression segment before said impression segment registers with any other plate segment, whereby fresh sheets lare fed onto said impression cylinder continuously at equal intervals and whereby printed sheets are discharged from said impression cylinder continuously at equal intervals, and whereby each of sheets carried by the impression cylinder is caused-to register with each of the printing plates in the same predetermined sequence and beginning with the same color.

3. A multi-color printing press comprising a single impression cylinder and at least one plate cylinder each having segments of equal peripheral length in the surfaces thereof adapted rto register substantially in tangency with each other, the circumferential length of the surfaces of the impression and plate cylinders each being an aliquot multiple, greater than unity, of the length of a segment, the circumferential length of a plate cylinder and the circumferential length of the impression cylinder being unequal by one segment length, means for rotating said impression and plate cylinders at the same peripheral speed, means including a plurality of printing plates positioned in said plate cylinder segments for printing a plurality of colors greater than the number of plate cylinders, means for retaining a sheet to be printed *on each segment of the impression cylinder, a feeding station past which each impression cylinder segment passes as the impression cylinder rotates, means for feeding sheets consecutively to an arithmetical progression of said impression cylinder segments passing said feeding station, the number of consecutive impression cylinder segments skipped between one segment which receives a fresh sheet and the next segment receiving a fresh sheet being one less than the number of plate segments 'on a single plate cylinder, means for discharging a sheet from its impression segment after it has registered with each of the printing segments on the printing cylinders, means for feeding a fresh sheet to be printed on said vacated impression segment before said impression segment registers with any other plate segment, said feeding i4 station being positioned adjacent said impression cylinder adjacent substantially the lowermost point of said impression cylinder, and a discharge station adjacent said impression cylinder spaced slightly 'below the uppermost point of said impression cylinder, both said feeding and discharge stations being positioned laterally of one side of a vertical plane through the axis of the impression cylinder, and the points of tangency of said plate cylinders with said impression cylinder being positioned laterally of the opposite side of said vertical plane.

4. A multi-color printing press comprising a single impression cylinder and at least one plate cylinder each having segments of equal peripheral length in the surfaces thereof adapted to register substantially in tangency with each other, the circumferential length of the surfaces of the impression and plate cylinders each being an aliquot multiple, greater than unity, of the length 'of a segment, the circumferential length of a plate cylinder and the circumferential length of the impression cylinder being unequal by one segment length, means for rotating said impression and plate cylinders at the saine peripheral speed, means including a plurality of printing plates positioned in said plate cylinder segments for printing a plurality of colors greater than the number of plate cylinders, means for retaining a sheet to be printed on each segment of vthe impression cylinder, a feeding station past which each impression cylinder segment passes as the impression cylinder rotates, means for feeding sheets consecutively to an arithmetical progression of said impression cylinder segments passing said feeding station, the number of consecutive impression cylinder segments skipped between one segment which receives a fresh she-et and the next segment receiving a fresh sheet being one less than the number of plate segments on a single plate cylinder, means for discharging a sheet from its impression segment after it has registered with each of the printing segments on the printing cylinders, means for feeding a fresh sheet to be printed on said vacated impression segment before said impression segment registers with any other plate segment, said feeding station being positioned adjacent said impression cylinder adjacent substantially the lowermost point of said impression cylinder, and a discharge station adjacent said impression cylinder spaced slightly below the uppermost point of said impression cylinder, both said feeding and discharge stations being positioned laterally of one side of a vertical plane through the axis or the impression cylinder, the points of tangency of said plate cylinders with said impression cylinder being positioned laterally of the opposite side of said vertical plane, and the plate cylinder carrying .the last printing segment to register with a sheet before it is discharged from said impression cylinder being positioned tangent to said impression cylinder at a point spaced from said discharge station a distance, along the periphery of said discharge cylinder, at least the length of one segment, whereby the sheet to be discharged is completely free of engagement .of any printing plate before the rst portion of the sheet begins to be discharged from the impression cylinder.

5. A multi-color printing press comprising a single impression cylinder and a single plate cylinder having equal segments in the surfaces thereof adapted to register with each other, the peripheral length of the surfaces of the impression. and plate cylinders each. being an aliquot multipla greater than unity, oi the length of a segment, the periplierallength ci said: impression cylinder coinp4 'sing threes said. segments: analthat of the plate cylinder comprising foursaid segments, means for rotating said.. impression and plate cylinders. at the same peripherall speed, a printing plate in each said. platev cylinder seg,- ments, Lor printing a different. color. inlL, means for. retaining av sheet to loev printed on each seg.- rnenti of the impressioncylinder, a. ieecling4 station past which each impression cylinder segment passes as the impression. cylinder. rotates, means for feeding sheets consecutively to an arithmetical. progression oi said impression cylinder segments. passing said feeding station, the number of consecutive impression cylinder segments skipped. hetween one segment which, receives a `fresh sheet and the next segment receiving a fresh sheet being three, means for discharging` a sheet roin its impression segment,r after it has registered' with-each `of the segments. onthe plate cylinder, ineens for feeding a fresh sheet .to ne printed on said vacated impression segment before said. impression segment registers with any other plate segment, whereby fresh sheets are feti` onto said impression cylinder continuously at equal intervals and whereby printed sheets are discharged from said impression cylinder ccntinuously at equal intervals, and wherebyeach of the sheets carried "ey the impression cylinder is caused to register with each of. the printing plates in theV same predetermined sequencev and beginningl with the saine color.

5. A multi-color printing press comprising a single. impression cylinder and a pair of plate cylinders, said plate cylinders having equal segments in thesuriaces thereof adapted to register with equal segments in the surface of the inipression cylinoterL the peripheral length or the surfaces oi' the impression and plate cylinders each being an aliquot multiple, greater than unity, of the length of a segment, the peripheral length of said impression cylinder including. three said segments and that of. each plate cylinder' i6 including two saidsegments, means for rotating' said.4 impression andplate. cylinders at the same peripheral speed, aA plurality of` printing plates on said' plate cylinders for printing. f2 plurality of. colors. greater than the number of plate cylinclers, means for retaining a sheet to be printed on each segment of. the impression. cylinder, a feeding station past which eachV impression cylinder segment passes as the impression cylinder rotates, means for feeding sheets consecutively to any arithmetical progression of said impression cylinder segments passing said feeding station, the number of impression cylinder segments skipped between one segment which receives a fresh sheet anti the next seginent receivingl a resh sheet being one, means for discharging; a sheet from its impression segment ait-er it has registered with each or" the segments on. the plate cylinders, ineans for feeding a fresh sheet to be printed on said: vacatedY impression segment heiore sai-cl impression segment registers with any other plate segment, whereby fresh sheets; are fed onto impression cylinder continuously at equal intervals and whereby printed sheets are discharged from saiol impression cylinder continuously at equal intervals, and whereby each of the sheets carried by the impression cylinder is caused toA register with each of the printing plates in the saine predetermined sequence and. beginning with the saine, color. J RUSSELLPARRISH.

Relerenees Cited in the le of this patent UNITED STATES Il?'IELV'I'Sy Number Name Date 5l7,907 lNendte Apr. 10', 1894 5i7,908 Wendte Apr. 10, 189e 519,461 Wendte May 8,v 1894 519,462 Wenclte May 8, 189eV 1,075,575 JohnsonV Oct. 14, 1913 1,326,562 Barber Dec. 30', 1919 2,054,215 Colville sept. i5, 193e 2,113,238 Smith li/iay 24,1938 

